css模糊背景

  width: 100%;
  height: 140rpx;
  background-image: -webkit-gradient(linear, left top, left bottom, from(rgba(255, 255, 255, 0)), to(#fff));
  background-image: linear-gradient(-180deg, rgba(255, 255, 255, 0) 0%, #fff 100%);
  position: absolute;
  left: 0;
  bottom: 0;
  z-index: 10;